Portable sawing device operating through impact



Jan. 30, 1951 P. MARCEROU PORTABLE SAWING DEVICE OPERATING THROUGHIMPACT Filed Jan. 22. 19 49 Pa tented Jan. 30, 1951 PORTABLE. SAWINGDEVICE OPERATING THROUGH IMPACT Paul Marcerou, Paris, France ApplicationJanuary 22, 1949, Serial No. 72,188 In France January 23, 1948 Claims.

a blade adapt d to op rate through im act and carrying at. each end apower unit de igned so as to im ress a reciprocating vertical movementto said blade while further means provide for the correct r lativepositioning of the two power units.

. A further object of the invention consists in that the power units areconstituted by pneumatic hammers, the piston rods of which are,

made ri id with the blade, preferably in a removable manner.

A still furth r obj ct of my invention consists in providing the powerunits laterally with means for taking hold of and carrying the device.

According to another feature of my invention, the blade is associat dwith weighting means adapt d to increase its ma s.

Accordin to a still further feature of the invention, said weightingmeans are c n titut d by a rigid cross-member that is guid d over thepower units and forms simultaneously a stay for the latter.

Further features and advantages of my invention will appear moreoverfrom the following description, reference b ing had to accompanyingdrawing the single figure of which is an elevational view of anarrangement according to the invention.

In the drawing, I designates a ste l blad or t e like. the lower edge ofwhich is fitted with striking memb rs 2 mad of a uita le hard mat rialsuch as tungsten carbide or the like. These members a sume any suitableshape and are secured to the blade I through hard-soldering or the like.i

The bolts 3 and 4 serve for rigidly securing the blade I to the pi tonrods 5 and t of pneumatic hammers i and 8 that are fed with compressedair in the usual manner throueh the agency of yielding pipesrespectively 9 and Ill.

The hammers I and 8 are provided with handle members i I and i2respectively through which it is possible to take hold of the sawingdevice to carry same and to displace it according to the requirements ofthe operation that is to be performed.

Springs illu trated respectively at 13 and it may be fitt d between theblade H and the lower end of the .body of the corresponding pneumatichammers 1 and 8.

The blade I is also rigid with a number of uprights I 5 the upper endsof which are rigidly connected to a rigid cross-bar !5. The members l5and it have for their object to increase the impact force. provid d withcorresponding guiding members I! and !8 that fitover a part of the outersurface of the cylindrical pneumatic hammers 1 and 8 so as to be guidedover same. Of course, the surface of the hammers 1 and 8 registeringwith the guiding members I? and I8 is designed so as to. allow a slidingthereof in said members without any too consid rable friction. The cros-bar l6 including its guiding members I! and i8 is of use not only forincreasing the moving mass of the system but also through the fact thatit constitutes a stay holding the hammers 'i and 8 reliably in theirrelative correct spaced relation,- shin.

The above arrangement o erates as follows: an operator takes hold ofeach pneumatic ham.- mer l or 3 through the corresponding handle I! and!2 aft r which the two operators place the blade I on the upper surfaceof the stone or the 2-5 like block !9 that it is desired to out. Whenthe pn umatic hammers l and 8 have started, the

blade I executes a rapid vertical reciprocating.

It should be noticed that the action of' the g striking members 2 isreinforced through the incr asing weight of the blade 2 as obtainedthrough the upri hts 5 and l 8, said increasing weight increasing theimpact energy.

' It should also be con idered that it is an easy matter to change theblade l after releasing the bolts 3 and 4.

Obviously the embodiment described hereinabove and illustrated in thedrawing is given out by way of a mere exemplification that may bemodified in any suitable manner as concerns the shape, material,arrangement and manner of mounting of its component members withoutunduly widening the scope of the invention. Thus the blade and thestriking members may assume any desired shape suiting the work to beperformed. Furthermore, the weightening of the blade may be obtainedthrough means different from tho e illustrated, such as the provision ofinserted heads. Similarly, the two pneumatic hammers may he stayed withreference to one The ends of the cross-bar 16 are- 3 another throughmeans different from those illustrated and described.

What I claim is:

l. A portable sawing device including an elongated saw blade adapted tooperate by impact of one longitudinal edge thereof with the object to besawed or cut; two power units disposed adjacent to the ends of theblade; means operably connecting said power units to the ends of saidblade whereby to impart to said blade a reciprocating movementperpendicular to its length; a rigid cross bar slidably engaging thepower units at the ends of said. cross bar for maintaining said powerunits synchronized with reference to each other; and at least twouprights spaced apart and rigidly interconnecting the blade and thecross bar and disposed perpendicularly to said blade and cross bar.

2. A portable sawing device including an elongated saw blade adapted tooperate by impact of one longitudinal edge thereof with the object to besawed or out, said blade having a series of hard striking elements fixedalong its enter one longitudinal edge; two pneumatic hammers eachincluding a hollow body and a reciprccable piston rod; means forremovahly securing the piston rods to the corresponding ends of theblade at an angle perpendicular to the length of the latter blade;handle members secured to the hollow body of each hammer; a heavy crossbar mounted with the ends thereof slidably engaging upon the outer bodysurfaces of the pneumatic hammers; and at least two uprightssubstantially parallel to the bodies of the hammers rigidlyinterconnecting the blade and cross bar externally of said hollowbodies.

3, A portable pneumatic sawing device including the combination, with anelongated saw blade adapted to operate by impact of one longitudinaledge thereof with the object to be sawed or cut, of two pneumatic hammercylinders spaced apart and mutually parallel; a pair of hammer pistonsreciprocable in the cylinders; piston rods extending rigidly from thepistons out through one end of each cylinder and rigidly secured to theends of the saw blade substantially at right angles to the longitudinaldimension thereof; elongated external means parallel to said saw-bladesslidably mounted at the ends thereof upon said cylinders; means formanipulating and manually holding the latter cylinders; and meansrigidly securing said saw blade and said elongated means together inspaced apart relation to and from a movable rigid unit effective tomaintain both pistons in operative unison.

4. A portable pneumatic sawing device including the combination, with anelongated saw blade adapted to operate by impact of one longitudinaledge thereof with the object to be sawed or cut, of two pneumatic hammercylinders spaced apart and mutually parallel; a pair of hammer pistonsreciprocable in the cylinders; piston rods extending rigidly from thepistons out through one end of each cylinder and rigidly secured to theends of the saw blade substantially at right angles to the longitudinaldimension thereof; a rigid cross bar substantially parallel to said sawblade having both ends thereof slidably enveloping the cylindersadjacent to the other end of each; manual means on the intermediateportions of said cylinders for manipulating and holding the latter; anda plurality of rigid connecting bars secured at the ends thereof to saidsaw blade and said cross bar intermediate said cylinders andinterconnecting said saw blade and cross bar into a reciprocating rigidunit.

5. A portable pneumatic sawing device including the combination, with anelongated saw blade adapted to operate by impact of one longitudinaledge thereof with the object to be sawed or cut, of two pneumatic hammercylinders spaced apart and mutually parallel and each having an open endand a closed end; a pair of pneumatic hammer members forming pistonsreciprocable in the cylinders; piston rods extending rigidly out fromthe pistons through the open ends of said cylinders and secured to theends of the saw blade substantially at right angles to the longitudinaldimension thereof; a rigid cross bar having the ends therof slidablylooped about said cylinders adjacent to the closed ends of the latter;means fixed on said cylinders for manipulating and manually holding suchcylinders; and means secured to said saw blade and to said cross bar forspacing them apart in parallelism and maintaining said blade and crossbar and piston rods, in a;

movable rigid unit, the closed ends of said cylinders having connectionsfor receiving a supply of compressed air for operating said device.

PAUL MARCEROU.

REFERENCES CITED The following references are of record in the -file ofthis patent:

UNITED STATES PATENTS Number Name Date 247,569 Maxim Sept. 27, 1881600,856 Brinkman Mar. 22, 1898 1,882,906 Renfer Oct. 18, 1932 2,152,193Johanning Mar. 28, 1939 2,188,318 Siderits Jan. 30, 1940 FOREIGN PATENTSNumber Country Date 691,527 Germany May 29, 1940'

